letters testamentary

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun plural A document issued by a probate court identifying the executor of a will and evidencing his or her authority to administer the estate in accordance with the terms of the will.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a legal document from a probate court or court officer informing you of your appointment as executor of a will and empowering you to discharge those responsibilities